the best from rhubarb
have a large rhubarb plant with huge leaves but the stalks are not
turning red. We've tried removing some of the outside leaves to
expose the stalks to more light, but it has made no difference.
The garden gets full sunlight and is sheltered.
have a continual problem with leaves on our rhubarb turning yellow
and wilting. When living in Hamilton, our plants were lush with
large juicy stalks. Apart from the odd sprinkle of fertiliser and
watering, they flourished. But not so in Papamoa, where we have
a very sandy soil. Even after trying several doses of potash, general
fertiliser and plenty of water, the plants never produce stalks
of any great size with many turning yellow and dying before reaching
grows best in a relatively cool climate - it can tolerate temperatures
as low as minus 15°C in winter. It also needs a plentiful supply
of water during the growing season and generous feeding, but good
drainage is also essential.
It's quite common for
the stalks not to turn red and there's not always an obvious answer
as to why this happens. Some experts say lack of light, others say
high temperatures while the stalk is growing, yet other factors
such as high nitrogen fertilisers could also play a part. There
is also a colour difference between varieties.
You can grow rhubarb
in warm areas, but generally the stalks do seem to be redder on
plants grown in cooler parts of the country. But once cooked, the
green stalks are just as nice to eat as red ones, though less attractive
on the plate.
There are a few diseases
that can cause problems with rhubarb and they tend to occur most
when drainage is poor or when temperature and humidity are high.
Yellowing and wilting of the leaves could simply be lack of water
at crucial times - the broad leaves need copious amounts of moisture
in summer. Or it could be a fungal disease. Check the crown of the
plant at the base of the leaves close to soil level for white fungal
growth or rot. If you find any, it's best to remove the plant completely
and buy a new, healthy one to plant elsewhere in the garden.
Other tips are to feed
regularly in the growing season with a high potassium fertiliser
and to remove any flowering stems as soon as they appear. It is
also worth remembering that rhubarb can tolerate shade, so you don't
have to plant it in a sunny spot.
Gardener, Issue 202, 2006, Page 31
Reproduced with permission from the former Weekend Gardener magazine. The views expressed here are not necessarily those of the RNZIH.